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81.
探讨了影响连续固相增粘产品活性的因素,提出了控制主反应器的温度、氮气流量、基础切片的端羧基、氮气露点等主要因素,实现生产的平稳控制,从而保证产品黏度的稳定。 相似文献
82.
氨法处理硫酸装置尾气生产亚铵的实践 总被引:1,自引:0,他引:1
介绍用氨法处理硫酸装置尾气生产亚硫酸铵的工艺流程、控制指标、主要设备和生产运行情况。实践表明,氨法SO2吸收率高,可实现装置尾气达标排放,但也存在产品品位较低的问题。对问题进行了分析并提出改进意见。 相似文献
83.
甲醛法测定铵盐含氮量 总被引:6,自引:0,他引:6
对甲醛法测定铵盐含氮量进行了研究,提出采用百里酚酞和酚酞混和指示剂进行测定。该法简单、快速、准确,能满足生产实际和样品检验需要。 相似文献
84.
85.
S. Yonemochi A. Sugiyama K. Kawamura T. Nagoya R. Aogaki 《Journal of Applied Electrochemistry》2004,34(12):1279-1285
Novel air purification materials were fabricated by the application of a magnetic field. In a magnetic field perpendicular to a copper plate, nickel particles with a diameter of 10 m were arranged to form numerous pillar-like structures on the matrix surface, and copper as a binder was deposited onto the three-dimensional surface. The total surface area of the pillars and the matrix increased with the magnetic flux density, up to about 800 cm2 per cm2 of the original matrix surface at 6.2 T. After successful codeposition of TiO2 particles on the fabricated materials by electroplating, their photocatalytic activities were evaluated on the basis of the removal efficiency of nitrogen oxides (NO
x
), which are some of the most hazardous air pollutants. It was concluded that the samples with the pillar-like structures had two opposite characteristics: large surface area as a positive effect and shadowing against ultraviolet (UV) irradiation as a negative effect. However, total photocatalytic activity increased to twice as much as that of the flat sample by improving the UV irradiation method and the preparation condition of the materials 相似文献
86.
Soil incubation studies were undertaken in controlled environment cabinets at 15°C to investigate the effect of increasing application rates of calcium ammonium nitrate (CAN) on net nitrification in two grassland soils. Granular CAN was applied to the surface of freshly collected, moist soil, at a rate equivalent to 0, 100, 200, 400, 800 and 1600µg NH
4
+
-N and NO
3
-
-N per gram of oven dry soil. In half the treatments finely ground CaCO3 was incorporated into the moist soil to raise the starting pH. Changes in soil mineral N and pH were measured at weekly intervals up to six-weeks. The most probable number (MPN) technique was used to enumerate the NH
4
+
-N and NO
2
-
-N oxidizers at the beginning and end of the incubation.At low rates of CAN application there was considerable NH
4
+
-N oxidation to NO
3
-
-N during the incubation of both soils. Lime stimulated this N transformation. At high application rates (i.e. 800 and 1600 ppm) there was little change in NH
4
+
-N or NO
3
-
-N on either soil during the 6 week incubation, in the presence or absence of lime. The rate of NO
3
-
-N produced peaked at 5.6 and 3.8 mg NO
3
-
-N kg–1 d–1 on soil 1 and 2 respectively, in the presence of lime. Above a level of 400 ppm CAN (equivalent to 38 kg N ha–1) the rate of NO
3
-
-N produced decreased. The higher rate of net nitrification in soil 1 compared with soil 2 was probably due to a higher number of nitrifying bacteria. Although high rates of CAN decreased the nitrifying activity of both soils there was little difference between treatments in the actual numbers of NH
4
+
-N and NO
2
-
-N oxidizers determined by the MPN technique.The results showed that the rate of granular CAN applied to the soil surface can influence the local activity of nitrifying bacteria and subsequent N transformations. At application rates of CAN generally used agriculturally for grass production, it is likely that net nitrification of the NH
4
+
-N in the fertilizer granule will be inhibited. 相似文献
87.
P. Muthuswamy C. R. Ranganathan V. Murugappan P. Santhy G. Ramanathan 《Nutrient Cycling in Agroecosystems》1990,23(3):135-140
A mathematical model has been proposed for predicting the changes in soil nitrogen status due to continuous fertilization in a continuous cropping sequence. The model also enabled the prediction of the steady state of soil nitrogen for a specified fertilizer practice.The model was applied to six years nitrogen availability data of four fertilizer practices in finger millet-maize-cowpea sequence followed in the Long Term Fertilizer Experiments conducted at Tamil Nadu Agricultural University, Coimbatore, India. The agreement between the predicted soil nitrogen status by the model and the actuals was proved by employing reliability index. 相似文献
88.
Slow growth and high seedling mortality limit direct seeding establishment of guayule (Parthenium argentatum G.). This study was conducted to assess seedling growth enhancement by the addition of different rates and forms of N fertilizers and Ca salts. Experiments were conducted in a greenhouse with cultivar 593 under both surface and subirrigated conditions using water low in salts (salinity of 0.8 dSm–1, SAR of 5.0 and 10 mg Ca L–1). Under surface-irrigated conditions, seedling height and fresh plant weight increased with N application to the irrigation water to 70 mg L–1. The best seedling growth was observed when (NH4)2SO4 was added in combination with CaCl2 or CaSO4. Progressively less growth was observed by addition of (NH4)2SO4 alone, CO(NH2)2 plus CaSO4, CO(NH2)2 alone and Ca(NO3)2. When seedlings were subirrigated, however, the best growth was observed with Ca(NO3)2. Intermediate growth was obtained with (NH4)2SO4 plus CaSO4 and lowest growth rates with (NH4)2SO4 alone. These differential responses may be explained by the differences in leaching and volatile characteristics of the N forms. Growth enhancement from N and Ca additions increased with time with significant increases 45 days after seeding. Nitrogen application with Ca may be effective amendment in promoting subsequent growth of direct seeded guayule. 相似文献
89.
90.